1. Field of the Invention This invention relates to flexible inspection instruments for use in both industrial and medical applications and, more particularly, to an elongated, flexible, fiber-scopic inspection device having an improved control head with repositionable components.
Elongated tubular inspection devices, particularly such devices incorporating flexible fiber-optics, are often used to inspect sites which would not normally be visible to the human eye. One application of such tubular inspection devices is in the practice of medicine. For instance, a common form of such device, known as a flexible ureteroscope, is used for the inspection of the human ureter and kidney while a similarly structured device, known as a colonoscope, is used for the inspection of the colon.
The ureteroscope is conventionally used for a variety of functions such as observation of areas and presenting a working tool at the area for such things as removing ureteral or kidney stones, dislodgment or ultrasonic destruction of ureteral stones, taking biopsies, irradiating tumors with laser fibers, etc. The ureteroscope examination can involve the physician's placing the instrument in the body through the urethra, then into the bladder, then through one of the ureteral tubes and then, if necessary, into the kidney itself. This can usually be a long and potentially torturous path through several organs of the body.
The inspection instrument generally has a control head forming a proximal end and a flexible tubular shaft, the end of which forming a distal end. The physician observes target areas through an eyepiece in the control head. Generally, the ureteroscope is provided with a bundle or bundles of optical fibers which bring light to its objective end, the end which is placed adjacent the area to be examined, and a bundle or bundles of light transmitting fibers through which an image of the examined area is transmiited back to the eyepiece. The ureteroscope can generally further incorporate a channel which provides a conduit for providing washing fluid to the site under examination as well as for the introduction of accessory devices to the site such as a biopsy forceps.
The flexible tubular shaft extending between the proximal end and the distal end of the flexible instrument generally has a variety of components passing therethrough. The shaft may have such components as a fiber bundle, a working channel and distal end control wires. The tubular shafts can also have a variety of cross sectional shapes as is seen from U.S. Pat. Nos. 1,958,656; 2,120,996; 3,368,552; 3,792,701 and 3,918,438.
The control head of a flexible ureteroscope is generally capable of serving many purposes including housing the optical eyepiece assembly, providing an entry for a light carrier from a light source, housing a deflection control system for moving and controlling the distal end and providing an entry for tools and fluids to enter into the control head and be transported to the objective end by means of a working channel.
A problem arises in using presently available devices in that the control head of such devices are unalterable fixtures having rigid components such as a rigid entry block and rigid light carrier entry. The physician, however, must generally twist and turn the ureteroscope while it is being inserted into the patient to properly navigate a path to the target area. As a result, the light carrier entry to the instrument and wash/instrument entry at the control head can often be in an awkward position in which to effectively work. If the operator tries to reposition the control head he will probably lose his observation point in which to view the target area. If the instrument entry or the light carrier entry of the control head are in an awkward or hindering position the operator is nonetheless compelled to operate the instrument in this position because to attempt to move or twist the control head would result in a loss of sight of the target area and thus result in a loss of time in which to relocate the target area.
Hence, in the prior art, the operator generally was compelled to operate the instrument in the position in which the target area had been located. This problem is particularly acute in the flexible medical endoscopes such as ureteroscopes, cystoscopes, nephroscopes and choleodoscopes.